The lingzhi mushroom is a polypore mushroom belonging to the genusGanoderma. Its red-varnished, kidney-shaped cap gives it a distinct appearance. When fresh, the lingzhi is soft, cork-like, and flat. It lacks gills on its underside, and instead releases its spores via fine pores. Depending on the age of the mushroom, the pores on its underside may be white or brown.[1]

Lingzhi mushroom is used in traditional Chinese medicine.[2][3] In nature, it grows at the base and stumps of deciduous trees, especially that of the maple. Only two or three out of 10,000 such aged trees will have lingzhi growth, and therefore its wild form is extremely rare. Today, lingzhi is effectively cultivated on hardwood logs or sawdust/woodchips.

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Taxonomy and ecology

It is part of a species complex that encompasses several fungal species. The most common and closely related species are Ganoderma lucidum (see also Scytalidopepsin B) and Ganoderma tsugae. There are multiple species of lingzhi encompassed within the Ganoderma lucidum species complex and mycologists continue researching the differences among species within this complex.[4]

With the advent of genome sequencing, the genus Ganoderma has undergone taxonomic reclassification. Prior to genetic analyses of fungi, classification was done according to morphological characteristics such as size and color. The internal transcribed spacer region of the Ganoderma genome is considered to be a standard barcode marker.[8]

Varieties

It was once thought that Ganoderma lucidum generally occurred in two growth forms: a large, sessile, specimen with a small or nonexistent stalk, found in North America, and a smaller specimen with a long, narrow stalk found mainly in the tropics. However, recent molecular evidence has identified the former, stalkless, form as a distinct species called G. sessile, a name given to North American specimens by William Alfonso Murrill in 1902.[4][9]

Environmental conditions play a substantial role in the lingzhi’s manifest morphological characteristics. For example, elevated carbon dioxide levels result in stem elongation in lingzhi. Other formations include antlers without a cap, which may also be related to carbon dioxide levels. The three main factors that influence fruit body development morphology are light, temperature, and humidity. While water and air quality play a role in fruit body development morphology, they do so to a lesser degree.[10]

In the wild, lingzhi grows at the base and stumps of deciduous trees, especially that of the maple.[12] Only two or three out of 10,000 such aged trees will have lingzhi growth, and therefore it is extremely rare in its natural form. Today, lingzhi is effectively cultivated on hardwood logs or sawdust/woodchips.[13]

Young sporocarp

Grown lingzhi Mushroom

Depending on environmental or cultivation conditions lingzhi may resemble antlers, with no umbrella cap.

History

The word lingzhi (靈芝) was first recorded in a fu (賦; “rhapsody; prose-poem”) by the Han dynastypolymathZhang Heng (CE 78–139). His Xijing fu (西京賦) (Western Metropolis Rhapsody) contains a description of the 104 BCE Jianzhang Palace of Emperor Wu of Han that parallels lingzhi with shijun (石菌; “rock mushroom”): “Raising huge breakers, lifting waves, That drenched the stone mushrooms on the high bank, And soaked the magic fungus on vermeil boughs.”[14] The commentary by Xue Zong (d. 237) notes that these fungi were eaten as drugs of immortality.

The Shennong bencao jing (Divine Farmer’s Classic of Pharmaceutics) of c.200–250 CE, classifies zhi into six color categories, each of which is believed to benefit the qi, or “life force”, in a different part of the body: qingzhi (青芝; “Green Mushroom”) for the liver, chizhi (赤芝; “Red Mushroom”) for the heart, huangzhi (黃芝; “Yellow Mushroom”) for the spleen, baizhi (白芝; “White Mushroom”) for the lungs, heizhi (黑芝; “Black Mushroom”) for the kidneys, and zizhi (紫芝; “Purple Mushroom”) for the Essence. Commentators identify the red chizhi, or danzhi (丹芝; “cinnabar mushroom”), as the lingzhi.

Chi Zhi (Ganoderma rubra) is bitter and balanced. It mainly treats binding in the chest, boosts the heart qi, supplements the center, sharpens the wits, and [causes people] not to forget [i.e., improves the memory]. Protracted taking may make the body light, prevent senility, and prolong life so as to make one an immortal. Its other name is Dan Zhi (Cinnabar Ganoderma). It grows in mountains and valleys.[15][16]

While Chinese texts have recorded medicinal uses of lingzhi for more than 2,000 years, a few sources erroneously claim its use can be traced back more than 4,000 years.[17] Modern scholarship accepts neither the historicity of Shennong, “Divine Farmer”, (legendary inventor of agriculture, traditionally c. 2737–2697 BCE) nor that he wrote the Shennong bencao jing.[citation needed]

The (1596) Bencao Gangmu (Compendium of Materia Medica) has a Zhi (芝) category that includes six types of zhi (calling the green, red, yellow, white, black, and purple mushrooms of the Shennong bencao jing the liuzhi (六芝; “six mushrooms”) and sixteen other fungi, mushrooms, and lichens, including mu’er (木耳; “wood ear”; “cloud ear fungus“, Auricularia auricula-judae). The author Li Shizhen classified these six differently colored zhi as xiancao (仙草; “immortality herbs”), and described the effects of chizhi (“red mushroom”):
{{Quote|text=It positively affects the life-energy, or Qi of the heart, repairing the chest area and benefiting those with a knotted and tight chest. Taken over a long period of time, the agility of the body will not cease, and the years are lengthened to those of the Immortal Fairies.[18][19]

芝 (Chih) is defined in the classics as the plant of immortality, and it is therefore always considered to be a felicitous one. It is said to absorb the earthy vapors and to leave a heavenly atmosphere. For this reason, it is called 靈芝 (Ling-chih.) It is large and of a branched form, and probably represents Clavaria or Sparassis. Its form is likened to that of coral.[20]

The Bencao Gangmu does not list lingzhi as a variety of zhi, but as an alternate name for the shi’er (石耳; “stone ear”, Umbilicaria esculenta) lichen. According to Stuart and Smith,

[The 石耳 Shih-erh is] edible, and has all of the good qualities of the 芝 (Chih), it is also being used in the treatment of gravel, and said to benefit virility. It is specially used in hemorrhage from the bowels and prolapse of the rectum. While the name of this would indicate that it was one of the Auriculariales, the fact that the name 靈芝 (Ling-chih) is also given to it might place it among the Clavariaceae.[20]

The name of the lingzhi fungus has a two thousand-year-old history. The Old Chinese name 靈芝 was first recorded during the Han dynasty (206 BC – 9 AD). In the Chinese language, língzhī (灵芝) is a compound. It comprises líng (灵); “spirit, spiritual; soul; miraculous; sacred; divine; mysterious; efficacious; effective)” as, for example, in the name of the Lingyan Temple in Jinan, and zhī (芝); “(traditional) plant of longevity; fungus; seed; branch; mushroom; excrescence”). Fabrizio Pregadio notes, “The term zhi, which has no equivalent in Western languages, refers to a variety of supermundane substances often described as plants, fungi, or ‘excrescences’.”[22]Zhi occurs in other Chinese plant names, such as zhīmá (芝麻; “sesame” or “seed”), and was anciently used a phonetic loan character for zhǐ (芷; “Angelica iris”). Chinese differentiates Ganoderma species into chìzhī (赤芝; “red mushroom”) G. lucidum, and zǐzhī (紫芝; “purple mushroom”) G. japonicum.

The Oxford English Dictionary (OED) gives the definition, “The fungus Ganoderma lucidum, believed in China to confer longevity and used as a symbol of this on Chinese ceramic ware.”,[28] and identifies the etymology of the word as Chinese: líng, “divine” + zhī, “fungus”. According to the OED, the earliest recorded usage of the Wade–Giles romanization ling chih is 1904,[29] and of the Pinyinlingzhi is 1980.

In addition to the transliterated loanword, English names include “glossy ganoderma” and “shiny polyporus”.[30]

Japanese

The Japanese word reishi (霊芝) is a Sino-Japanese loanword deriving from the Chinese língzhī (灵芝; 靈芝). Its modern Japanese kanji, 霊, is the shinjitai (“new character form”) of the kyūjitai (“old character form”), 靈. Synonyms for reishi are divided between Sino-Japanese borrowings and native Japanese coinages. Sinitic loanwords include literary terms such as zuisō (瑞草, from ruìcǎo; “auspicious plant”) and sensō (仙草, from xiāncǎo; “immortality plant”). The Japanese writing system uses shi or shiba (芝) for “grass; lawn; turf”, and take or kinoko (茸) for “mushroom” (e.g., shiitake). A common native Japanese name is mannentake (万年茸; “10,000-year mushroom”). Other Japanese terms for reishi include kadodetake (門出茸; “departure mushroom”), hijiridake (聖茸; “sage mushroom”), and magoshakushi (孫杓子; “grandchild ladle”).

Korean

The Korean name, yeongji (영지; 靈芝) is also borrowed from, so a cognate with, the Chinese word língzhī (灵芝; 靈芝). It is often called yeongjibeoseot (영지버섯; “yeongji mushroom”) in Korean, with the addition of the native word beoseot (버섯) meaning “mushroom”. Other common names include bullocho (불로초, 不老草; “elixir grass”) and jicho (지초; 芝草). According to color, yeongji mushrooms can be classified as jeokji (적지; 赤芝) for “red”, jaji (자지; 紫芝) for “purple”, heukji (흑지; 黑芝) for “black”, cheongji (청지; 靑芝) for “blue” or “green”, baekji (백지; 白芝) for “white”, and hwangji (황지; 黃芝) for “yellow”.

Thai

The Thai word het lin chue (เห็ดหลินจือ) is a compound of the native word het (เห็ด) meaning “mushroom” and the loanword lin chue (หลินจือ) from the Chinese língzhī (灵芝; 靈芝).

Vietnamese

The Vietnamese language word linh chi is a loanword from Chinese. It is often used with nấm, the Vietnamese word for “mushroom”, thus nấm linh chi is the equivalent of “lingzhi mushroom”.

A 2015 Cochrane database review found insufficient evidence to justify the use of G. lucidum as a first-line cancer treatment. It suggests that G. lucidum may have “benefit as an alternative adjunct to conventional treatment in consideration of its potential of enhancing tumour response and stimulating host immunity.”[33] Existing studies do not support the use of G. lucidum for treatment of risk factors of cardiovascular disease in people with type 2 diabetes mellitus.[34]

Culinary

Coffee with Lignzhi Extract

Because of its bitter taste, lingzhi is traditionally prepared as a hot water extract product.[21] Thinly sliced or pulverized lingzhi (either fresh or dried) is added to boiling water which is then reduced to a simmer, covered, and left for 2 hours.[35] The resulting liquid is dark and fairly bitter in taste. The red lingzhi is often more bitter than the black. The process is sometimes repeated to increase the concentration. Alternatively, it can be used as an ingredient in a formula decoction, or used to make an extract (in liquid, capsule, or powder form). The more active red forms of lingzhi are far too bitter to be consumed in a soup.[citation needed]

Lingzhi is now commercially manufactured and sold. Since the early 1970s, most lingzhi is cultivated. Lingzhi can grow on substrates such as sawdust, grain, and wood logs. After formation of the fruiting body, lingzhi is most commonly harvested, dried, ground, and processed into tablets or capsules to be directly ingested or made into tea or soup. Other lingzhi products include processed fungal mycelia or spores.[35]